need advice for deal with LBS

I have an etiquette question for you folks who work at bike shops, or who might have an opinion on this.

The owner of my LBS was kind enough to let me test-ride some of his own employee-purchased 2010 wheels for a week. I can't afford them, unfortunately, but was thinking I could make it work if I offered to buy the same wheelset I'm borrowing for whatever he got it for with his employee purchase (minus the cassette, tires, tubes, of course). He could then buy himself a brand new wheelset.